Brake device for cycles



May 21a FL KORMANN 23mm BRAKE DEVICE FOR CYCLES Filed June 28, 1938 17Karma??? Patented May 21, 1940 I I UNITED STATES PATENT OFFICE BRAKEDEVICE-FOR. CYCLES Franz Kormann, Graz, Germany, assignor of one-thirdto Otto E. Miiller, Philadelphia, Pa., and one-third to Christian Prell,Asch, Czechoslovakia Application June 28, 1938, Serial No. 216,378 InAustria July 25, 1936 1 Claim. (Cl. 192-5) This invention relates toimprovements in back said bearing rings, and one or more pawls 4 which pa in ra s r y s a d s mi ar y p rare pivotally secured to only thebearing ring ated vehicles of the kind in which the chain 2 and, underthe action of a spring, are in mesh wheel or the like, which is in rigidc nn with the toothing of the ratchet wheel 3. Thus 5 W the pedal Cranksy means of the crank all these parts are combined in a self-containedshaft, is provided with a ball looking or ratchet rim or wheel of alarger inside diameter than gearing Which is Operative in 13118 backpedalling corresponds to the outside diameter of the crank directiononly and the ratchet wheel of which axle bearing and which may besecured subseis mounted freely rotatable on the chain wheel quently to alaterally projecting flange 6a of the 10 or the like and is connectedwith a front wheel hub of the chain wheel 6 of the chain drive for in-10 brake and a back wheel brake by separate Bowstance by means of ascrew-threaded extension den cables or the like, both brakes beingoperated 5 on one of said bearing rings. If desired, the simultaneouslyin the moment of back pedalling back pedalling brake may be fixed to thechain in view of the operation of the pawls or balls. wheel in anothermanner, for instance by means lhe known arrangements of this kind are ofscrews. 15

mounted directly on that end of the crank shaft The ratchet wheel 3 isprovided with a radially of the pedals to which the chain wheel is notseextending arm 9, to which the ends of two Bowcured. Thus the drawbackarises that the crank den cables I and 8 are secured; the Bowden shaftof the pedals has to be made longer than the cables passing along theframe of the cycle to crank shaft of a common cycle. Therefore it is thefront wheel brake Ill and to the back wheel 20 impossible to secure theknown back pedalling brake ll respectively. brakes to a common cyclewithout providing it The pawls 4 slide over the teeth of the ratchetwith a crank shaft of greater length, which, of wheel 3 when riding onthe cycle in the ordinary course, is a drawback for subsequently fittingway. However in the moment of pedalling back a back pedalling brake to acycle of usual conin the direction of the arrow shown in Fig. 3, the 25struction. pawls 4 engage the ratchet wheel 3 and thus pull In backpedalling brakes of the kind above deback the Bowden cables I and 8,thereby applying scribed, this drawback is overcome according to thebrakes l0 and II. the present invention by combining the bearing What Iclaim isrings, the ratchet wheel and the pawls to an inde- A backpedalling brake for cycles comprising 30 pendent ring-shaped unit of alarger inside diamfront and rear wheels, brake members associated eterthan corresponds to the outside diameter of with said wheels, a chaindrive for one of said the crank axle bearing, said unit being adapted towheels including a toothed chain wheel, a crank be secured to the chainwheel in such a manner axle and a bearing for said axle, a bearing ring5 that it surrounds the crank axle bearing. having an inside diameterlarger than the out- In view of this construction neither the crank sidediameter of said bearing, means securing shaft nor the distance betweenboth cranks is inthe bearing ring to the chain wheel on the sidefluenced in any way, so that the pedal cranks adjacent the bearing, asecond bearing ring havof the cycle remain quite unchanged in spite ofing screw thread connection with the first menthe addition of the backpedalling brake. tioned ring and forming therewith a self con- 40 Onemode of carrying out the present inventained rim, an internally toothedratchet rim tion is illustrated by way of example on the acrotatablymounted between the bearing rings, companying sheet of drawings inwhichpawls freely movable between the rings and con- Fig. 1 shows acycle with back pedalling brake. nected with one of the latter andengageable with Figs. 2 and 3 show in cross section and in partthe teethof the ratchet rim to rotate the latter 45 sectional side Viewrespectively the back pedalonly in the back pedalling direction ofmovement ling brake constructed according to the present of said crankaxle, a radial arm on the ratchet invention. rim, and freely accessibleconnections between The back pedalling brake comprises two intersaid armand the brake members of the front screwed bearing rings I and 2, aninternally and rear wheels. 50

toothed ratchet wheel 3 which is mounted freely FRANZ KORMANN.

rotatable, preferably on ball bearings, between

